FileMapping library docs

Language/Haskell/GhcMod/FileMapping.hs

@@ -20,10 +20,30 @@ import Control.Monad.Trans.Maybe
 import GHC
 import Control.Monad
 
-loadMappedFile :: IOish m => FilePath -> FilePath -> GhcModT m ()
+{- | maps 'FilePath', given as first argument to take source from
+'FilePath' given as second argument. Works exactly the same as
+first form of `--map-file` CLI option.
+
+\'from\' can be either full path, or path relative to project root.
+\'to\' has to be either relative to project root, or full path (preferred)
+-}
+loadMappedFile :: IOish m
+               => FilePath -- ^ \'from\', file that will be mapped
+               -> FilePath -- ^ \'to\', file to take source from
+               -> GhcModT m ()
 loadMappedFile from to = loadMappedFile' from to False
 
-loadMappedFileSource :: IOish m => FilePath -> String -> GhcModT m ()
+{- |
+maps 'FilePath', given as first argument to have source as given
+by second argument.
+
+\'from\' may or may not exist, and should be either full path,
+or relative to project root.
+-}
+loadMappedFileSource :: IOish m
+                     => FilePath -- ^ \'from\', file that will be mapped
+                     -> String -- ^ \'src\', source
+                     -> GhcModT m ()
 loadMappedFileSource from src = do
   tmpdir <- cradleTempDir `fmap` cradle
   to <- liftIO $ do
@@ -59,7 +79,16 @@ mkMappedTarget _ _ taoc (Just to) =
   return $ mkTarget (TargetFile (fmPath to) Nothing) taoc Nothing
 mkMappedTarget _ tid taoc _ = return $ mkTarget tid taoc Nothing
 
-unloadMappedFile :: IOish m => FilePath -> GhcModT m ()
+{-|
+unloads previously mapped file \'file\', so that it's no longer mapped,
+and removes any temporary files created when file was
+mapped.
+
+\'file\' should be either full path, or relative to project root.
+-}
+unloadMappedFile :: IOish m
+                 => FilePath -- ^ \'file\', file to unmap
+                 -> GhcModT m ()
 unloadMappedFile = getCanonicalFileNameSafe >=> unloadMappedFile'
 
 unloadMappedFile' :: IOish m => FilePath -> GhcModT m ()